Field of the Invention
This invention relates to a method for the measurement of the concentration of a substance which plays an important biochemical role or of various substances derived from a living body (hereafter "analyte") using a protein capable of specifically binding the substance through competitive reaction. This invention further relates to an analysis film comprising a reaction layer--where the aforesaid analyte is competitively reacted with a protein capable of specifically binding the same--and a signal is formed by undergoing a change in proportion to concentration of the analyte is received. The term "signal" refers to a detectable change that is directly or indirectly indicative of the presence and/or concentration of a substance being analyzed, i.e., the analyte, or a reaction or decomposition product of the analyte.